The Federation quietly lays the groundwork through embedded anthropological research and quiet diplomatic contacts before the big reveal. In the episode, it's explained that this has been done ever since the first contact with the Klingons went horribly wrong. Trekkies, the comment section below will let you correct everything I've said that's wrong.

“First Contact,” a 1991 episode of “Star Trek: The Next Generation,” , concerns the moment a previously isolated civilization is first contacted by the United Federation of Planets. In this episode, the race about to be contacted are the Malcorians, a suspiciously humanoid society of religious suburbanite dweebs with a fondness for Communist office buildings and John Lennon spectacles. They consider themselves the center of the universe.

Gene Roddenberry's famous television show, in its various incarnations, has always put humankind — and its fellow humanoid aliens with accented foreheads or ears — on a temporal spectrum of development, from primitive and tribal to federated and cosmopolitan. It has signposted the places we can go if we embrace the better angels of our nature. But it has never shied away from what happens when a species isn't ready to make the leap.

That may be where we are with the Schengen states today.

The Limits of Free Movement

The Schengen Zone

This overcomes the problem of what is called "homeland nationalism," the idea that a national state has power and influence over its ethnic compatriots even if they're citizens of other countries. Interwar Germany, post-Yugoslav Serbia, and modern day Russia all have made such claims to have influence, and ultimately territorial control, over people beyond their borders.

There are two reasons homeland nationalism is so pernicious. One, it justifies international aggression, most infamously Hitler's seizure of lands with ethnic Germans in them outside Germany's interwar borders. And two, its ultimate logic is ethnic cleansing: after the Second World War, most of Germany's neighbors evicted their German populations to prevent such revisionism from ever happening again.

The beauty of Schengen is in the free and unfettered movement of people across borders within the zone. If you're German, you can travel to the Czech Republic, get a job there, live there, and get married there. But you're still German: you can't vote in the Czech Republic and there's no chance Germany will use your presence there to try to annex Czech territory. By allowing for movement that doesn't threaten the hard-won self-determination of peoples, Schengen accounts for, and accommodates, the persistence of national identity. Rather than confronting nationalism directly, Schengen steps around it. It's elegant.

Refugees turn this on its head. A refugee is in practice from outside the Schengen zone, and is by definition unable to return to his or her homeland for fear of persecution. Most are settled, often permanently, in countries that offer them asylum. Sometimes this includes the granting of citizenship. For the states of Europe, which often labored for centuries to construct a national polity, the prospect of such a massive demographic upheaval is inherently destabilizing. It's the opposite of Schengen, which protects national identity while allowing for a cosmopolitan, integrated continent.

Refugee flows and the arrival in large numbers of the "other" awakens the slumbering nationalist. As refugee flows increase, so too does support for the likes of Pegida, Golden Dawn, the National Front, the UK Independence Party, and others. And while the demonization of refugees is abhorrent, the long-term demographic implications are real: the number of displaced Syrians alone, counting internally displaced persons, exceeds the population of many smaller European nations. That's just Syrians, and just today. Consider the relative demographic trajectories of European states (with flat or declining populations), and compare them to the Middle East or sub-Saharan and Sahelian Africa (with populations that double every 20-25 years) and you begin to see the potential scale of the change.

Morally, our common humanity should render this irrelevant. Syrian refugees are suffering through no fault of their own, Europe has the physical capacity to take them in, and should do so. But what if the act of doing so spells electoral defeat for pro-European politicians, and leaves Europe in the hands of Marine Le Pen and Nigel Farage? What if the act of doing so ends Schengen and breaks up the EU?

All it took to hammer home the fear of the "other" was one fake Syrian passport — again, a fake passport — found on the body of one of the Paris attackers. This is the context behind Manuel Valls's comments this week that Europe "cannot take anymore refugees." This is not true in a factual sense: physically, of course Europe can. Nor is this comment reasonably based in the fear of refugees bringing terrorism: these refugees are overwhelmingly fleeing terrorism, and in any case all the Paris attackers appear to have been European. Rather, what Valls is saying is that the European body politic cannot take any more refugees without an anti-European nationalist backlash. Valls is practicing what he believes is the art of the possible.

Ready or Not?

Spoiler alert! and I mean it, stop reading this unless you've seen the episode. It's a good one, except for yet another pointless and bizarre sexual excursion for Commander Riker.

In "First Contact", the Malcorian security chief is so opposed to interplanetary integration that he attempts to stage his own assassination and blame Riker for it. When the Malcorian President learns of this, he makes a heartbreaking decision: he decides his own people are not ready for first contact, and tells the Enterprise crew to come back in a few generations to try again.

It's a devastating ending: everyone involved knows that they will likely never see each other again, and an entire planet will be denied the benefits and wonders of the cosmos, possibly for generations or even centuries. The President's top scientific aid actually abandons her planet and runs off with the Enterprise rather than be consigned to a future of such terrestrial boredom. But it's arguably the right decision: the planet is almost ready for first contact, but not quite. First contact could embolden religious hardliners, "planetists" (if you will), and other reactionary elements to strike down much of what the society has, to that point, achieved.

Martin Luther King, Jr. famously wrote in Letter From a Birmingham Jail that "[t]his 'wait' has almost always meant 'never'." But given the incremental but very real progress of European integration in the postwar era, what if Europe today is like the Malcorians ... almost ready for this moment, but not quite? What if we are faced with an awful choice: limit migration and leave huge numbers of refugees out in the cold, or put the decades of remarkable integration Europe has achieved so far at intolerable risk? Sometimes, we face a moral responsibility but are not up to the challenge. Is this one of those times?